Interior Painting Cost Calculator
Start with room dimensions or an area you have already measured. Calculate paint for the selected coats, then build an itemized budget for paint, optional primer, preparation and job labor.
Continue your project estimate
Estimate paint gallons first →Connect paint quantity with the actual project price
Interior painting cost depends on paintable area, coats, product coverage, paint price, preparation and labor. If you need gallons first, use the Paint Calculator and then apply the material and labor rates that match the job.
Separating quantity from cost makes it easier to compare DIY material-only scenarios with contractor labor scenarios.
- Use measured paintable area.
- Model coats and product coverage before pricing.
- Keep prep or repair work in fixed extras when relevant.
How this estimate works
In room mode, each room uses wall area = 2 × (length + width) × height, less the entered door and window openings. Selected ceilings add length × width. Identical rooms can share one group; add another group when dimensions differ.
Paintable area is multiplied by coats and the material allowance, divided by the product coverage per gallon, then rounded up to whole gallons. The calculator assumes one paint product across those areas. Calculate separate estimates when colors or products cannot share the same purchase quantity.
total = whole paint gallons × paint price + optional primer cost + paintable area × job labor rate + preparation allowance + fixed extras
The labor rate covers the complete job on the measured area. Changing coats changes paint quantity, without multiplying a labor quote that already includes those coats.
Example
Two identical 12 × 10 ft rooms with 8 ft walls, 32 sq ft of openings per room and both ceilings included give 880 sq ft of paintable area. Two coats at 350 sq ft/gallon with a 10% material allowance require 6 whole gallons of paint.
With illustrative prices of $40/gallon paint, one primer coat at 300 sq ft/gallon and $25/gallon, $1.50/sq ft job labor, $0.20/sq ft preparation and $50 fixed extras, the budget is $1,886: $340 materials, $1,320 painting labor and $226 preparation/extras. These are calculation examples, not current local price estimates.
Interior painting budget questions
Can I use my home's floor area?
Floor area alone does not measure walls. Use room dimensions and wall height, or enter the paintable wall and selected ceiling area directly.
Does the result include trim, doors and repairs?
Only the areas and prices you enter are included. Trim, doors, substantial repairs, equipment or minimum contractor charges can use fixed extras when they are separately quoted.
Does paint-and-primer mean I always need a separate primer?
No. The separate primer option is off initially. Check the product instructions and surface requirements before including it. If primer is already in a quote, do not price it again.
Where does the coverage example come from?
BEHR's quantity guide gives a 250–400 sq ft/gallon range for specified products. The editable 350 sq ft setting is a planning example within that range. Your chosen product, surface and application can require a different value. Reference reviewed October 4, 2026.
Related tools
Paint Quantity Calculator · Drywall Cost Calculator · Project Budget Workspace · Compare Contractor Quotes